Bosch DS151i Passive Infrared Request-to-Exit (REX) Motion Sensor, 8 x 10 Ft Coverage, Black

The Bosch DS151i is a black passive infrared (PIR) request-to-exit detector with an 8 x 10-foot coverage area, dual Form C relay outputs, and selectable fail-safe or fail-secure operation. Designed for single- and double-door access control applications, it detects approaching occupants and signals compatible door release equipment. The detector operates on 12 or 24 VAC/VDC, draws approximately 26 mA at 12 VDC, and features adjustable relay latch timing from 0.5 to 64 seconds. Its surface-mount housing supports wall or ceiling installation, internal vertical aiming, and configurable detection patterns.

Bosch DS151i Black PIR Request-to-Exit Motion Detector for Access Control

The Bosch DS151i is a passive infrared request-to-exit (REX) motion detector designed for automatic door release in commercial electronic access control systems. Part of the Bosch DS150i Series, this black detector identifies movement within a defined area near a controlled doorway and activates its relay outputs to signal a compatible access control panel or electric locking device. The DS151i provides a typical detection coverage area of 8 feet by 10 feet (2.4 x 3 meters), accommodating single-door and double-door installations where an occupant approaches from the secured side. Its passive infrared sensing technology detects changes in thermal energy caused by movement, allowing the detector to initiate a request-to-exit signal without requiring the user to press a button or present an access credential. Common applications include controlled office entrances, commercial buildings, healthcare facilities, educational institutions, and interior security doors equipped with compatible electromagnetic locks or electric strikes.

The Bosch DS151i incorporates two Form C relay contact sets with selectable fail-safe and fail-secure operating modes, providing configurable switching for access control interfaces and electrically operated locking hardware. Each relay provides common, normally open, and normally closed contacts, allowing installers to select the appropriate signaling arrangement for the connected equipment. One relay includes protection against inductive voltage spikes, making it suitable for appropriately rated inductive loads when wired according to Bosch's installation instructions. The detector features adjustable relay latch timing from 0.5 to 64 seconds, with selectable intervals of 0.5, 1, 2, 4, 8, 16, 32, and 64 seconds. Configurable resettable and non-resettable timing modes allow the relay to remain active based on continued movement or to deactivate after a predetermined interval. An externally visible activation LED provides local indication of motion detection and assists technicians during installation, alignment, and operational testing.

The DS151i operates from a 12 or 24 VAC/VDC low-voltage power source and draws approximately 26 mA at 12 VDC under the manufacturer's published nominal specifications. Bosch's installation documentation identifies a higher current requirement during alarm operation, which must be considered when calculating power supply capacity. Its compact housing measures 6.25 inches wide, 1.5 inches high, and 1.5 inches deep (159 x 38 x 38 mm) and is manufactured from high-impact ABS plastic with a black finish. The detector supports surface mounting on a wall, ceiling, or compatible door frame, with internal vertical aiming to direct its sensing pattern toward the intended approach area. Its wrap-around detection pattern and optional lens masking allow installers to customize coverage and reduce unwanted activations caused by movement outside the desired exit path. The manufacturer's specified operating temperature range is -20 F to 120 F (-29 C to 49 C), with additional environmental restrictions applicable to UL-listed installations. The optional Bosch TP161 black trim plate provides a finished appearance when mounting the detector over a standard single-gang electrical box.

The Bosch DS151i is designed for integration with commercial access control panels, electromagnetic door locks, electric strikes, and compatible door release control circuits. Its dual relay outputs and configurable timing options allow the detector to support different request-to-exit configurations while accommodating single-door or paired-door applications. The detector is UL 294 listed for access control system applications, with applicable ULC-S319 and CE compliance documented by Bosch. Proper installation requires positioning the detector to recognize an occupant approaching the controlled exit while minimizing activation from adjacent pedestrian traffic or movement outside the protected area. The DS151i is not intended to serve as the sole or primary means of emergency egress; installations must incorporate the required independent door release mechanisms and comply with applicable life safety and building codes. Unlike the Bosch DS150i, which features a light gray enclosure, the DS151i uses a black housing while retaining the same fundamental PIR sensing and relay control capabilities. Its combination of 8 x 10-foot PIR coverage, dual Form C relays, configurable timing, selectable power-loss behavior, and flexible mounting provides a compact request-to-exit solution for professionally installed electronic door security systems.